Competing ν = 5/2 fractional quantum Hall states in confined geometry

Abstract

The 5/2 fractional quantum Hall state has captured the fascination of the scientific and nonscientific community, because of proposals to use it for quantum computation. These proposals have been based on the premise that the quasiparticles in this state have non-Abelian statistics. Experiments supporting both Abelian 5/2 state and non-Abelian 5/2 state have been reported, and no consensus has been reached. Using measurements of tunneling between edge states, we suggest that both the Abelian and non-Abelian states can be stable in the same device but under different conditions. Our discovery resolves the inconsistencies between existing experiments. More importantly, the knowledge of the competition between ground states is important for maintaining non-Abelian statistics in application to topological quantum computation.